CN110108444B - An experimental device for sulfur deposition in sulfur-bearing natural gas pipelines - Google Patents

Abstract

The invention relates to an experimental device for sulfur deposition in a sulfur-containing natural gas pipeline, comprising a gas storage system, a loop system and a sulfur-dissolved agent filling system, wherein the gas storage system and the dissolved-sulfur agent filling system are installed on the loop system. The loop system includes a detachable pipe section, and the detachable pipe section is of a detachable structure to facilitate experiments. After the experiment, it can be fixed by a fixing device, and the sulfur deposits can be heated and melted. The invention can analyze the influence of variables such as specific time, temperature, pressure, flow rate, and surface roughness of the pipe wall on the sulfur deposition law, and at the same time, it can study the removal effect of different types of sulfur-dissolving agents on sulfur deposits, and can simulate and analyze well Sulfur deposition in real high-sulfur natural gas pipelines.

Description

An experimental device for sulfur deposition in sulfur-bearing natural gas pipelines

technical field

The invention belongs to the technical field of pipeline transportation of natural gas, in particular to an experimental device for sulfur deposition in a sulfur-containing natural gas pipeline.

Background technique

High-sulfur gas fields in China have large reserves and wide distribution, such as Yuanba Gas Field and Puguang Gas Field. Among them, the average H ₂ S content of Puguang Gas Field is 15.16%, and the problem of sulfur deposition in gathering and transportation systems during the extraction of sulfur-containing natural gas is becoming more and more prominent. During the transportation of high-sulfur natural gas, under the influence of pressure, temperature, flow rate and other factors, sulfur precipitation and sulfur deposition will occur. Light yellow powdery and viscous sulfur deposits are often found on the pipe wall of the gathering and transportation system, which is a serious threat. Pipeline system safety. It is mainly reflected in the following aspects: (1) The precipitated and deposited sulfur components are easy to block the instrument pressure pipes, metering orifice plates and other equipment on the pipeline, resulting in distorted test results, inaccurate data collected, and huge potential safety hazards. (2) After sulfur deposition occurs on the pipe wall, the gas flow area will become smaller, which will increase the pipeline pressure drop and energy consumption, and reduce the gathering and transportation efficiency. (3) The sulfur deposits on the pipe wall will change the electric field, magnetic field, temperature field and other environments on the pipe wall surface, accelerate the corrosion of the pipe wall, and threaten the safety of the material structure.

The influencing factors of sulfur deposition are mainly divided into two parts: thermodynamics and kinetics, including gas temperature, temperature difference between gas and tube wall, flow rate, and tube wall roughness. Some previous research results show that the saturated solubility of elemental sulfur increases with the increase of hydrogen sulfide content, and increases with the increase of pressure and temperature under the condition of certain components. And the solubility of element sulfur in the range of 50-80 ℃ increases the fastest with the increase of temperature; below 30 ℃, the solubility of element sulfur increases little with the increase of temperature. However, there are few experimental devices that can test and study the effects of thermodynamic and kinetic factors on the sulfur deposition law in the produced gas from high-sulfur gas fields, which seriously restricts the in-depth study of the sulfur deposition law and characteristics.

SUMMARY OF THE INVENTION

In order to solve the above existing technical problems, the present invention provides a sulfur deposition experimental device for a sulfur-containing natural gas pipeline, which can effectively study the influence mechanism of thermodynamic and kinetic factors on the sulfur deposition law, and at the same time, can evaluate and study the effect of different sulfur-dissolving agents on the sulfur deposition law. Elimination of sulfur deposits.

The technical scheme adopted in the present invention is as follows:

An experimental device for sulfur deposition in a sulfur-containing natural gas pipeline, comprising a gas storage system, a loop system and a sulfur-dissolving agent filling system, wherein the gas storage system is a high-pressure gas tank, and the loop system includes a loop pipeline and a loop pipeline. The upper part is connected with the high-pressure gas tank and the dismantling pipe section, and a first control valve, a first pressure gauge, a compressor, a second pressure gauge and a dissolved sulfur agent filling system are arranged between one side of the high-pressure gas tank and the dismantling pipe section. A second control valve is arranged between the sulfur-dissolving agent filling system and the loop pipeline; the two ends of the detachable pipe section are respectively provided with a temperature-controlled water bath inlet and a temperature-controlled water bath outlet, and the temperature-controlled water bath inlet and the temperature-controlled water bath outlet are arranged between the temperature-controlled water bath inlet and the temperature-controlled water bath outlet. A first check valve, a mass flow meter, a second check valve and a fifth control valve are arranged between the disassembled pipe section and the other side of the high-pressure gas tank in sequence; the loop pipeline A bypass pipeline is connected in parallel at both ends of the first check valve and the second check valve, and a third control valve and a fourth control valve are respectively arranged between the bypass pipeline and the loop pipeline.

Beneficial effects of the present invention:

(1) It can simulate the sulfur deposition environment of on-site gas pipelines, and specifically study the influence of variables and factors such as pressure, gas temperature, temperature difference between gas and pipe wall, gas flow rate, pipe wall roughness, and pipe wall material on sulfur deposition;

(2) The detachable pipe with detachable structure is used as the experimental pipe section, which is convenient for weighing and sampling the sediment, and provides convenience for further analysis of the characteristics of the sediment. At the same time, the detachable pipe section can be processed into different pipe wall roughness and material replacement. The pipe section makes the experimental operation flexible and changeable;

(3) The device is equipped with a sulfur-dissolving agent filling system, which can effectively evaluate and study the removal effect of different types of sulfur-dissolving agents on sulfur deposits;

(4) The pipeline system of the device is equipped with an explosion-proof electric heating belt, which can control the temperature at a specified value. When the experiment is over, the pipe wall can be heated, so that the sulfur deposits attached to the pipe wall can be melted and flowed away.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the present invention;

Fig. 2 is the structural representation of high pressure gas tank in Fig. 1;

Fig. 3 is a schematic diagram of the structure of the disassembled pipe section of Fig. 1;

Fig. 4 is A-A sectional side view in Fig. 3;

Fig. 5 is the structural schematic diagram of the vertical sampling process of dismantling the pipe section in Fig. 1;

Fig. 6 is the top view of the fixed bracket in Fig. 5;

FIG. 7 is a schematic structural diagram of the sulfur-dissolving agent filling system in FIG. 1 .

In the figure, 1, high pressure gas tank; 2, first control valve; 3, first pressure gauge; 4, compressor; 5, second pressure gauge; 6, second control valve; 7, dissolved sulfur agent filling system ;8. Temperature-controlled water bath inlet; 9. Detachable pipe section; 10. Temperature-controlled water bath; 11. Water pipe; 12. Temperature-controlled water bath outlet; 121. Pipeline pressure relief valve; Valve; 141, bypass pipeline; 15, first check valve; 16, flow meter; 17, second check valve; 18, fourth control valve; 19, fifth control valve; 20, high pressure gas tank 21. Gas return pipeline; 22. Electric heating device; 23. Exhaust gas and waste liquid discharge pipeline; 24. High-pressure gas tank control valve I; 25. Gas filling pipeline; 26. High-pressure gas tank control valve II; 27. Gas outflow pipeline; 28. Pressure gauge of high-pressure gas tank; 29. Safety relief valve; 30. Outer layer of jacket; 31. Inner layer of jacket; 32. Tighten nut; 33. Tighten screw; 34. Ring pipeline; 35 , is the first clamping and fixing ring; 36, the second clamping and fixing ring; 37, the fixing bracket; 38, the molten sulfur deposit; 39, the beaker; 40, the nut; ;43, liquid level gauge; 44, storage tank safety relief valve; 45, thermometer; 46, storage tank pressure gauge; 47, relief valve; 48, relief pipeline; 49, storage tank control valve; 50, liquid pump ; 51, storage tank flowmeter; 52, atomizer; 53, the filling port of dissolved sulfur agent.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

Example

As shown in the figure, an experimental device for sulfur deposition in a sulfur-containing natural gas pipeline includes a gas storage system, a ring channel system and a sulfur-dissolving agent filling system. The gas storage system is a high-pressure gas tank 1, and the ring channel system includes a ring channel system. The pipeline 34, the loop pipeline is connected with the high-pressure gas tank and the dismantling pipe section 9, and the first control valve 2, the first pressure gauge 3, the compressor 4, the first control valve 2, the first pressure gauge 3, the compressor 4, the first control valve 2, the first pressure gauge 3, the first Two pressure gauges 5 and sulfur-dissolving agent filling system 7, a second control valve 6 is provided between the sulfur-dissolving agent filling system 7 and the loop pipeline; And the temperature-controlling water bath outlet 12, the temperature-controlling water-bath inlet 8 and the temperature-controlling water-bath outlet 12 are connected to the temperature-controlling water bath 10 through the water pipe 11; Check valve 15 , mass flow meter 16 , second check valve 17 and fifth control valve 19 141, a third control valve 14 and a fourth control valve 18 are respectively provided between the bypass pipeline 141 and the loop pipeline 34.

The high-pressure gas tank 1 is a vertical tank, and the high-pressure gas tank body 20 is respectively connected with a gas return line 21, a waste gas and waste liquid discharge line 23, a gas filling line 25 and a gas outflow line 27. The liquid discharge pipeline 23 is provided with a high-pressure gas tank control valve I 24, the described gas filling pipeline 25 is provided with a high-pressure gas tank control valve II 26, and an electric heating device is installed inside the described high-pressure gas tank body 20 22. The electric heating device 22 can use a ceramic electric heating ring, which has the advantages of stable performance, anti-corrosion, fast heating, uniform heat dissipation, good insulation performance, high pressure resistance, etc. The upper part of the high-pressure gas tank body 20 is installed with a high-pressure gas tank Pressure gauge 28 and safety relief valve 29.

The high-pressure tank body 20 is made of sulfur-resistant corrosion-resistant materials, the gas return line 21 is a pipeline for the sulfur-containing natural gas to be circulated back to the high-pressure gas tank after passing through the loop system, and the electric heating device 22 has the functions of explosion-proof and temperature control. , the natural gas in the high-pressure storage tank can be heated to a specified temperature, the purpose of the waste gas and waste liquid discharge line 23 and the high-pressure gas tank control valve I 24 is to regularly clean up the residual gas and liquid in the high-pressure gas tank, and the gas added The injection line 25 and the high-pressure gas tank control valve II26 are used to control the injection of sulfur-containing natural gas into the tank. The sulfur-containing natural gas is the gas sampled on site, so that the experimental results can truly reflect the on-site sulfur deposition. Sulfur natural gas enters the loop system, the high-pressure gas tank pressure gauge 28 can monitor the gas pressure in the tank, and the safety relief valve 29 can play an overpressure protection role.

The compressor 4 can be assembled with multiple compressors in series according to the requirements of the experimental conditions to realize multi-stage supercharging.

The detachable pipe section 9 and the loop pipeline 34 are connected by flanges. The detachable pipe section 9 is set by the outer jacket 30 to form a jacket structure outside the inner jacket 31. The temperature-controlled water bath inlet 8 and the temperature-controlled water bath outlet are 12 communicates with the inner cavity of the jacket.

The outer jacket 30 is provided with a temperature-controlling water bath inlet 8 and a temperature-controlling water-bath outlet 12 in the upper and lower directions of the same section. The annular space between it and the inner jacket 31 is for circulating water to flow, so as to control the wall temperature of the experimental pipe section.

The flange is connected and fixed by tightening the nut 32 and the tightening screw 33, and a sealing gasket is provided between the tightening nut 32, the tightening screw 33 and the flange.

The said loop pipeline 34 is wound with the explosion-proof electric tape 13, and the loop pipeline 34 is provided with a pipeline pressure relief valve 121.

The explosion-proof electric belt 13 has switch control and heating indicator light components, which is convenient for operation, and the explosion-proof electric belt 13 can control the temperature of the pipe wall to a specified value. The bypass pipeline 141 is convenient for cleaning the sulfur deposits in the pipeline, ensuring that the melted sulfur deposits do not flow through the flowmeter, and reducing the adverse effect on the flowmeter. The flowmeter 16 is a mass flowmeter, and the first check valve 15 and the second check valve 17 are arranged on both sides of the flowmeter 16 to prevent the change of the gas flow direction from damaging the internal structure of the flowmeter.

The sulfur-dissolving agent filling system includes a sulfur-dissolving agent storage tank 42, the sulfur-dissolving agent storage tank adopts a horizontal structure, and a liquid level gauge 43, a storage tank safety pressure relief valve 44, a thermometer are installed on the dissolving sulfur agent storage tank 45. Tank pressure gauge 46, drain line 48, sulfur-dissolving agent filling port 3 and liquid pump 50, a drain valve 47 is installed on the drain line 48, and a storage tank is installed between the liquid pump 50 and the sulfur-dissolving agent storage tank 42. The tank control valve 49, the liquid pump 50 is connected with the atomizer 52 through the pipeline, the storage tank flow meter 51 is installed between the liquid pump 50 and the atomizer 52, and the atomizer 52 is communicated with the loop pipeline 34 through the second control valve 6 .

The sulfur-dissolving agent storage tank 42 is made of corrosion-resistant materials, the liquid level gauge 43 can monitor the liquid level of the sulfur-dissolving agent in the storage tank, the storage tank safety relief valve 44 plays an overpressure protection function, and the thermometer 45 The temperature of the dissolved sulfur agent in the storage tank can be monitored, the storage tank pressure gauge 46 can read the pressure in the storage tank, the drain valve 47 and the drain line 48 can remove the residual liquid in the storage tank, and the atomizer 52 The sulfur-dissolving agent can be changed into a mist and sprayed into the loop pipeline, so that the sulfur-dissolving agent can fully contact with the sulfur particles, and the effect of dissolving sulfur can be enhanced. Sulfur agent.

The detachable pipe section 9 is fixed by a fixing device after being disassembled. The fixing device includes a clamping and fixing ring and a fixing bracket 37. The fixing brackets are arranged on both sides of the clamping and fixing ring, and the clamping and fixing ring includes two arcs. The first clamping and fixing ring 35 and the second clamping and fixing ring 36, the ends of the first clamping and fixing ring 35 and the second clamping and fixing ring 36 are provided with mounting ears, and the mounting ears are provided with threaded holes, nuts and The screw rod passes through the threaded hole to fixedly connect the first clamping and fixing ring and the second clamping and fixing ring, so as to clamp the detachable pipe section.

After the detachable pipe section is fixed, a temperature-controlled water bath can be turned on, the detachable pipe section can be heated, and all the sulfur deposits deposited on the pipe wall are melted into the beaker for weighing and test analysis. In this way, the influence of variables such as specific time, temperature, pressure, flow rate, etc. on the sulfur deposition law can be analyzed to achieve the experimental purpose.

The operation process of the experimental study of sulfur deposition law is as follows:

The high-sulfur natural gas obtained from the natural gas pipeline on site is added to the high-pressure gas tank 1, the electric heating device 22 is turned on to heat the natural gas to the specified temperature, the first control valve 2 and the fifth control valve 19 are adjusted to be open, and the second control valve is adjusted. 6. The pipeline pressure relief valve 121, the third control valve 14, the fourth control valve 18, the high-pressure gas tank control valve I24, and the high-pressure gas tank control valve II26 are closed, and the temperature-controlled water bath 10 is opened to control the experimental pipe section. At the specified temperature, the first check valve 15 and the second check valve 17 are opened, the compressor 4 is started, and the natural gas is circulated in the pipeline system. By controlling the compressor power and the valve opening, the gas pressure and The flow rate, the temperature of the gas entering the experimental pipe section can be controlled by the electric heating device of the high-pressure gas tank, and the pipe wall temperature of the experimental pipe section can be controlled by the temperature-controlled water bath, thereby realizing the specific flow rate, gas temperature, gas temperature and pipe wall temperature difference, pressure Equal variables to study the law of sulfur deposition. In addition, the detachable experimental pipe section can be processed with pipe walls of different materials or surface roughness, which is convenient for replacement, so that the influence of surface roughness and material on sulfur deposition can be studied.

After the sulfur deposition experiment, close the first control valve 2 and the fifth control valve 19, close the compressor, and open the pipeline pressure relief valve 121 at the same time to discharge the gas remaining in the pipeline into a specific device for harmless treatment, Separate the detachable experimental pipe section from the loop system pipeline, place the experimental pipe section vertically and clamp it, turn on the temperature-controlled water bath 10, and heat the experimental pipe section, melt all the sulfur deposits 38 deposited on the pipe wall into the beaker 39, and weigh. weight and test analysis. In this way, the influence of variables such as specific time, temperature, pressure, flow rate, etc. on the sulfur deposition law can be analyzed to achieve the experimental purpose.

The operation process of the experimental study on the effect of the dissolved sulfur solvent is as follows:

To study the effect of dissolving sulfur agent on the removal of sulfur deposits on the pipe wall, first carry out a sulfur deposition experiment under specific conditions for a certain period of time, and then weigh the sulfur deposits in the experimental pipe section, and weigh the entire experimental pipe section during weighing. The mass of the sediment attached to the pipe wall is obtained by subtracting the mass of the pipe section when there is no sediment, and then the experimental pipe section is reconnected to the loop system to ensure that the relief valve 47 is closed, and the storage tank control valve 49 and No. 4 are opened. A control valve 6 turns on the liquid pump 50 and turns on the atomizer 52. At the same time, open the loop system again, so that the high-sulfur gas continues to circulate in the pipeline, and drive the atomized dissolved sulfur agent to flow together in the pipeline system. After a certain time, the loop system and the dissolved sulfur can be closed. The agent filling system was used, and the experimental pipe section was removed again to weigh the sediment. After comparison, the sulfur-dissolving effect of different types of sulfur-dissolving agents on the sulfur sediment can be obtained, and then the comparison and optimization can be made.

Claims (3)

1. A sulfur deposition experimental device for a sulfur-containing natural gas pipeline is characterized by comprising a gas storage system, an annular system and a sulfur dissolving agent filling system, wherein the gas storage system is a high-pressure gas tank (1), the annular system comprises an annular pipeline (34), the annular pipeline is communicated with the high-pressure gas tank and a detachable pipeline section (9), a first control valve (2), a first pressure gauge (3), a compressor (4), a second pressure gauge (5) and a sulfur dissolving agent filling system (7) are sequentially arranged between one side of the high-pressure gas tank and the detachable pipeline section, and a second control valve (6) is arranged between the sulfur dissolving agent filling system (7) and the annular pipeline; two ends of the detachable pipe section are respectively provided with a temperature-controlled water bath inlet (8) and a temperature-controlled water bath outlet (12), and the temperature-controlled water bath inlet (8) and the temperature-controlled water bath outlet (12) are communicated with a temperature-controlled water bath (10) through a water pipe (11); a first check valve (15), a mass flow meter (16), a second check valve (17) and a fifth control valve (19) are sequentially arranged between the detachable pipe section (9) and the other side of the high-pressure gas tank; a bypass pipeline (141) is connected in parallel at two ends of the first check valve (15) and the second check valve (17) on the loop pipeline (34), and a third control valve (14) and a fourth control valve (18) are respectively arranged between the bypass pipeline (141) and the loop pipeline (34);

at least one compressor (4) is arranged, and a plurality of compressors are installed in series;

the detachable pipe section (9) is connected with the loop pipeline (34) through a flange, the detachable pipe section (9) is sleeved outside the inner jacket (31) through the outer jacket (30) to form a jacket structure, and the temperature-controlled water bath inlet (8) and the temperature-controlled water bath outlet (12) are communicated with the inner cavity of the jacket;

an explosion-proof electric heating belt (13) is wound on the loop pipeline (34), and a pipeline pressure release valve (121) is arranged on the loop pipeline (34);

the sulfur dissolving agent filling system comprises a sulfur dissolving agent storage tank (42), the sulfur dissolving agent storage tank is of a horizontal structure, a liquid level meter (43), a storage tank safety pressure relief valve (44), a thermometer (45), a storage tank pressure gauge (46), a drainage pipeline (48), a sulfur dissolving agent filling port (3) and a liquid pump (50) are mounted on the sulfur dissolving agent storage tank, a drainage valve (47) is mounted on the drainage pipeline (48), a storage tank control valve (49) is mounted between the liquid pump (50) and the sulfur dissolving agent storage tank (42), the liquid pump (50) is connected with an atomizer (52) through a pipeline, a storage tank flowmeter (51) is mounted between the liquid pump (50) and the atomizer (52), and the atomizer (52) is communicated with a loop pipeline (34) through a second control valve (6);

the utility model discloses a detachable pipe section, including dismantlement formula pipe section (9), dismantlement formula pipe section is fixed by fixing device after dismantling, fixing device includes that the solid fixed ring of centre gripping and fixed bolster (37), and the fixed bolster sets up the both sides at the solid fixed ring of centre gripping, the solid fixed ring of centre gripping includes solid fixed ring (35) of two curved first centre gripping and solid fixed ring (36) of second centre gripping, and the tip of the solid fixed ring of first centre gripping (35) and the solid fixed ring of second centre gripping (36) is equipped with the installation ear, is provided with the screw hole on the installation ear, and nut and screw rod pass the screw hole with the solid fixed ring fixed connection of the.

2. The sulfur deposition experiment device for the sulfur-containing natural gas pipeline as claimed in claim 1, wherein the high-pressure gas tank (1) is a vertical tank, the high-pressure gas tank body (20) is respectively communicated with a gas return line (21), a waste gas and liquid discharge line (23), a gas filling line (25) and a gas outflow line (27), the waste gas and liquid discharge line (23) is provided with a high-pressure gas tank control valve I (24), the gas filling line (25) is provided with a high-pressure gas tank control valve II (26), the high-pressure gas tank body (20) is internally provided with an electric heating device (22), and the upper portion of the high-pressure gas tank body (20) is provided with a high-pressure gas tank pressure gauge (28) and a safety relief valve (29).

3. The experimental device for sulfur deposition in the sulfur-containing natural gas pipeline as claimed in claim 1, wherein the flange is fixedly connected with the tightening nut (32) and the tightening screw (33), and sealing gaskets are arranged between the tightening nut (32), the tightening screw (33) and the flange.

Images